Re: GSE Zero Length PDU

[Bernhard Collini-Nocker <bnocker@cosy.sbg.ac.at>]

Hello (again),

Kevin Kimmich schrieb:
> Hello,
> 
> We’re in the process of defining a system that will use GSE.
> 
> We are looking at cases that are ambiguous in the GSE specification. 
> One such case is how to deal with zero length PDUs. It’s possible, 
> though probably not advisable, for an encapsulator to send such a 
> packet.

on one side a zero length PDU (interpreted as having a valid protocol
header but empty payload) is not a "problem" for GSE rather than the
upper layer protocol(s) that handles the PDU. As long as the
GSE-Protocol-Type field is valid it will pass this "problem" to the
upper layer indicated by Protocol-Type.

On the other side (interpreting zero length PDU as having no header at
all) GSE would need a special Protocol-Type value to support transport
of it (nothing?). Currently only the test-extension-header (see RFC
4326, 5.1) could support this, but would prevent a receiver from
forwarding this (non-existing) data...

> Any advice on how to handle this case?

Combining this with your next question (DOCSIS over GSE) I would assume
that signalling is being carried in DOCSIS frames (as GSE PDUs) that
have only a header but no payload, in what case the first of above
options should work.

> Thanks,
> Kevin Kimmich

Regards,
Bernhard

> Senior Software Engineer
> 
> Efficient Channel Coding, Inc.
> 
> 
> 
> The University of Aberdeen is a charity registered in Scotland, No 
> SC013683.
> 


The University of Aberdeen is a charity registered in Scotland, No SC013683.